## Research subjects [2017]:

Part of my research focuses on novel
gluonic effects at high energies. Gluons are the force carriers of the
strong
interaction, which is one of the
four fundamental forces of Nature. The microscopic theory of the strong
interaction is the quantum theory
of quarks and gluons, called Quantum Chromodynamics (QCD). Unlike
Quantum Electrodynamics (QED, the
quantum theory of electrons and photons), QCD is a strongly interacting
theory and a highly
non-linear theory. As a result, it exhibits phenomena that are absent
in QED and that are more akin to those of strongly interacting systems
in condensed matter physics. These phenomena of QCD show up in extreme
circumstances, such as those in the early
universe or in ultra-relativistic collisions between
heavy ions and/or protons. Currently I am studying the properties of
gluons in such extreme conditions, with emphasis on their collective
behavior and on the appropriate theoretical description (in terms of
Wilson lines and loops).

Our knowledge of gluons has been instrumental in the discovery of
the Higgs boson and that may well be the case again for the discovery
of new physics beyond the Standard Model of elementary particles in the
future. However, so far we have no experimental indication for such new
physics, therefore, theoretical investigations will have to follow
general guiding principles such as the degree of symmetry and
naturalness of the theory. It turns out to be very hard to find highly
symmetric (but non-supersymmetric) theories that naturally, i.e.
without fine-tuning, lead to the Standard Model at low energies and
satisfy the extremely stringent experimental constraints on any new
physics. My aim here is to construct new symmetry breaking mechanisms
that can be implement in extensions of the Standard Model in a natural
way.